When a package is secured by a strap, the package is circumscribed by the strap so that the strap has overlapping portions. These overlapping portions are enclosed in a seal structure, the strap is tensioned to a pre-selected tautness about the package, the seal is crimped about the overlapping strap portions to secure the overlapping strap portions together, and the excess strap situated externally of the seal is cut off or sheared. In this manner continuous strap which may be supplied from a reel can be used.
Illustrative prior art tensioning and shearing tools include those shown in U.S. Pat. No. 3,150,694 to Meier wherein the shearing mechanism includes a driving cylinder-piston assembly which is energized by opening a valve so that air is supplied to the cylinder to move the piston and the piston rod. The strap is sheared along the edge of the seal without using a cutting block.
Another prior art tensioning and shearing tool is disclosed in U.S. Pat. No. 3,028,885 to Leslie et al., wherein a first handle is moved to actuate the tensioning mechanism, and a second handle is provided to operate the shearing mechanism. Shearing is effected by rotating the second handle, to which a cutter is pivotally connected, thereby severing the strap between the cutter blade and the straight cutting edge of a cutting block. The second handle is biased toward the off-position by a handle spring, but the second handle can be operated any number of times before a subsequent tensioning operation is initiated.